Control



March 20, 1934. w, J. BESLER CONTROL Filed April 24, 1931 INVENTOR. ZZdXfi ATTORNEYS. v

WWW/am J fies/er BY Patented Mar. 20, 1934 Q CONTROL William J. Besler, Oakland, Calif., assignor to Doble Steam Motors, Ltd., Reno, Nev., a corporation of Nevada Application April 24, 1931, Serial No. 532,511 Claims. (01. 122-448) My invention relates primarily to mechanism ondary inlet between the primary inlet and the for controlling generators of vapor such as steam outlet of the tube, together with means under conboilers. trol of a thermostat situated intermediate the In automotive practice in which steam prosecondary inlet and the outlet of the tube for sie pulsion is utilized, it is advantageous to employ multaneously controlling the introduction of feed a steam generator or boiler of the forced circufluid into the primary inlet of the tube and into lation type, that is, a boiler which comprises a relthe secondary inlet of the tube. atively long heated tube into one portion of which In the form of my invention disclosed in the fluid, such as water, is introduced and through drawing, there is provided a vapor generator or 10 the entire length of which the water traverses boiler 6 comprising a casing '7 within which a and emerges from the outlet end thereof as vapor, relatively long tube 3 is situated. -The tube is such as steam. It is customary to regulate the preferably formed into a number of convolutions proportions of heat and water or other fluid, so and is provided with a primary inlet 9 and an that the ultimately issuing fluid is super-heated. outlet 11. Flow of vapor or steam from the tube 5 It is desirable to maintain the temperature of the through the outlet 11 is controlled by a throttle issuing vapor substantially at a predetermined valve 12 in the customary fashion. value despite rapid and wide fluctuations in load In order to impart heat to the tube 8, the cas- 011 the boiler in q y of V p ss ing '7 is intersected by a Venturi tube 13 through therefrom. It is further desirable in automotive which a, draft of air is impelled by a blower 14.

2o practice t make t me hanis f r insur a The blower 14 is driven by an electric motor 16, relatively fixed temperature of issuing pO 948 and/or any other suitable motive unit, and is Simple as possible and u ject t little 0 110 1- effective to induce a current of air to flow through pervision. In certain practical installations of th t ri 13, aspirate fuel from a carburetor forced circulation boilers, the tube isapproxi- 17 d t emerge into the combustion space 18 25 mately 600 feet i len h and the time required at the top of the boiler casing 7 wherein the mixfor liquid to traverse the initial portion of the t i ignited by a. spark plug 21. The products tube and for the resulting vapor to traverse the of combustion pass over the convolutions of the fi portion of the tube comparatively g tube a and are exhausted through a flue 22.

It has heretofore been proposed to utilize a ther- In order that the tube 8 may be effective to 30 mostat situated adjacent theoutlet of the tube generate vapor I preferably afford a supply of for regulating the introduction of feed fluid into feed l q id, h as t therefon In t presthe inlet end of the tube. Such an arrangement m; instance, th i provided a source of feed is relatively unsatisfactory inasmuch as the time fluid h as water t nk 23 which is connected lag is so great between the introduction of feed by t 24 t a, water pump 26. The pump dis- 35 water into the foot of the tube and its effect on the charges through conduit 27 i t th primary v thermostat as to result in large fluctuations in the inlet 9 of t t b 8, Preferably the pump 26 is t p a i the ult mat ly issuin steemdriven b a steam engine 31 which is directly con- It therefore, an Object of y inventionto nected thereto and which receives steam through provide a control system which affords vapor of a conduit 32 extending t th utlet 11 of the relatively constant temperature from a generator, t 3, I practice, the capacity of the pump 26 especially from a generator of the forced oircuis usually such t t t is capable under fun t. latlon yp put of introducing into the tube 8 more feed fluid A h obj t f my inv n i n i to provide than can be heated to the desiredtemperature a Simplified Control SyStemunder maximum operation of the blower 14, al-

45 Another object of my invention is to provide though, if desired t pump may be of li it d 10 a con r syst which i t y ut mati a capacity so that it ceases to work above a predewhich requires no supervision. te -mi d pressure,

The foregding and other Objects attained In order to control the operation of the pump inthe embodiment of the invention shown inthe 26 d f th mower 14, t supply vapor from 50 drawing, i Which 1 'the outlet 11 at a substantially constant, prede- The figure is a diagram illustrating one form termined temperature, I preferably provide a of C n rol in accordance With y invention. thermostat 36. in thermal relation to the boiler In its preferred form, the control of my inventube 8 adjacent the final portion thereof. The tion comprises a relatively long tube having a prithermostat includes a rod 37 which is moved with 55 mary inlet adjacent one end thereof and a secrespect to the boiler casing 7 under variations in .110

temperature of the tube 8 and serves to actuate a pivoted rocker 39. At one extremity, the rocker 39 carries a contact 4l which is joined by a flexible lead 42 to a conductor 43. The conductor 43 extends to a contact 44 on a lever 46 influenced or controlled by a pressure cell 47 subject to pressure in the outlet 11. The contact 44 cooperates with a contact 49 joined by a wire 51 to a master switch 52.

Furnishing electromotive force for the electrical circuit is a storage battery 53, or other suitable source of electromotive force, one side of which is grounded as at 54 and the other side of which is connected by a lead 56 to the master switch 52. When the pressure in the tube 8 is below a predetermined value and when the master switch 52 is closed, current flows in the conductor 43 to the contact 41. If the contact 41 is in abutment with a cooperating contact 61 the current continues to flow through a lead 62 extending to one side of the electric motor 16, the other side of which is connected to ground by a wire 63, thus completing the circuit to the motor and causing the blower 14 to be driven.

As the blower is driven and products of combustion heat the tube 8, the temperature adjacent the thermostat 36 increases until it arrives at such a value that the thermostat rod 37 causes the rocker 39 to rotate on its pivot suificiently to separate the contacts 41 and 61, thus breaking the circuit to the blower motor 16 and causing a cessation of the heat supply to the boiler tube 8. By virtue of this arrangement the blower supplies heat to the boiler at all temperatures up to and including a predetermined temperature at which the contacts 41 and 61 separate, while above such predetermined temperature the blower 14 is not driven and the supply of heat is interrupted or stopped.

In order to control the supply of water or feed fluid to the tube 8, I preferably provide at the extremity of the rocker 39 a contact 71 which is adapted to cooperate with a contact '72 connected by a lead 73 .to the conductor 43. When the contacts 72 and '71 are in abutment, current flows into a lead 74 extending to an electromagnet or'sole- I noid 76 which is grounded, as at 7'7. The electromagnet '16 controls the operation of a valve '78 governing flow through the conduit 32 so that when the solenoid or electromagnet 76 is energized, steam generated withinthe tube 8 flows through the conductor 32 and to the steam engine 31 thereby causing the pump 26 to extract feed fluid from the reservoir or source 23 and introduce it through the conduit 2'7 and past a check valve 80 into the primary inlet 9 of the boiler tube 8.

SinceI have found by an extensive practice that the introduction of feed. fluid into the primary inlet 9 of the boiler in itself is not capable of producing a close regulation of the temperature of the issuing steam, I preferably provide a branch conduit 81 intersecting the conduit 27 adjacent the primary inlet 9 of the boiler tube, and extending to a secondary inlet 82 of the boiler tube 8. The secondary inlet is adjacent the thermostat 36 and is preferably between the thermostat and the primary inlet 9. In some of the claims the point" of entry of the secondary inlet is referred to. I It must be understood that this refers to the location, or place, or region, or situation of the inlet rather than exclusively to a mathematical "point. Since there is in practice a material pressure'drop between the pri-' mary inlet 9 of the boiler tube 8, and the secondary inlet 82 thereof, I find it advisable in most cases to insert in the branch conduit 81 not only a check valve but also a control orifice, generally designated 83. The control orifice 83 preferably comprises a standard coupling having a male unit 84 and a female unit 86 between which there is clamped a disc 87 provided with an aperture or orifice 88 therethrough. The size of the orifice 88 is fixed but by releasing the members of the coupling 83 and inserting discs comparable to the disc 87 but having different sized orifices 88 therethrough it is possible to provide the desired flow through the branch conduit 81. erably the proportion of the total feed fluid which flows through the branch conduit 81 is about ten percent. of the total flowing through the conduit 27 leaving a remainder of approximately ninety percent. to flow through the primary inlet 9.

By provision of the branch conduit 81 for introducing feed fluid into the secondary inlet 82 relatively close to the thermostat 36 a prompt effect is had on the thermostat so that as soon as the contacts 71 and '72 have closed, which preferably occurs slightly before the contacts 41 and 61 have opened, the valve 78 is opened, the engine 31 operates and the pump 26 introduces water or feed fluid through the primary inlet 9 and the secondary inlet 82 simultaneously and in the approxi mate proportions desired. The effect of the injection of the feed fluid is first on the thermostat 36 which is cooled markedly by the secondary water flowing into the inlet 82 and causes the thermostat rod 37 to move so that contacts 71 and 72 are separated thus breaking the circuit to the electromagnet 76 and stopping steam flow to the engine 31 whereupon the pump 26 ceases further pumping of water into the boiler tube 8. That is, flow occurs at the same time in conduits 9 and 82. It is initiated at the same time and terminated at the same time and can therefore be said to be in synchronism and in phase.

Depending upon operating conditions, the contacts '71 and 72 can open and close with greater or less rapidity and since they are usually adjusted with respect to the contacts 41 and 61 so that the contacts '71 and 72 close preferably at a first predetermined temperature. while the contacts 41 and 61 open at a second predetermined temperature which is a few degrees higher than the first predetermined temperature, the feeding of water into the boiler is rapidly intermittent. Under light loads it requires a relatively small amount of water introduced into the secondary inlet 82 to aifect the thermostat 36 quickly but under relatively heavy loads, particularly if the blower 14 increases materially the amount of heat supplied to the boiler, a relatively greater amount of water introduced through the secondary inlet 82 is required to reduce the temperature of the thermostat 36 sufl'iciently to cause the contacts 71 and '72 to separate. that is when relatively greater amounts of water are introduced through the secondary inlet 82 there is a corresponding increase in the introduction of the feed fluid into the primary inlet 9 so thatthe entire boiler is accommodated to the increase in load thereupon. When the load is reduced and the boiler is returned to a light load condition, any excess water which may have been introduced through the secondary inlet. 82 is promptly effective on the thermostat '36 and causes it to cool materially thereby'requiring a relatively long period of operation of the burner or boiler 14 before the thermostat 36 is again Pref- Under such conditions,

heated to such a value that the contacts 71 and 72 are again closed.

Under a condition in whch the supply of feed fluid to the secondary inlet 82 is not sufficient to cool the thermostat 36 despite the amount of heat being imparted thereto by the operation of the blower 14 the temperature of the thermostat 36,rises to the predetermined value sothat the rod 37 causes the rocker 39 to pivot and to separate the contacts 41 and 61 thereby stopping operation of the blower 14 and preventing an additional amount of heat being imparted to the boiler tube 3 until the temperature has again fallen to the predetermined value. Also, under the condition that the boiler pressure within the tube 8 rises to a predetermined value the pressure cell 47 causes the rocker 46 to separate the con-' tacts 44 and 49 thereby not only causing an interruption in the supply of heat by virtue of stopping the operation of the blower 14 but also deenergizing the electromagnetr'lfi so that the valve '78 is closed and further supply of feed water to the boiler is entirely interrupted.

In practice the preferred adjustment of the device is such, under a typical condition, that the pressure regulator is set for approxixnatelyl500 pounds per square men while the; contacts 41 and 61' are normally closedunder low temperatures but open at approximately 900'degrees Fahrenheit, while the contacts 71 and 72 are adjusted to close at approximately 890 sdegrees Fahrenheit. I have found in practice that with this adjustment and under .all variations in load and output of the boiler that the temperature varies substantially between the limits stated and does not surge appreciably beyond the limits indicated.

It is to be understood that I do not limit myself to the form of 'the control shown and described herein, as the invention, as set forth in the following claims may be embodied in a plurality of forms.

I claim: V

1. A control comprising a boiler tube having an inlet and an outlet, means for heating said tube, means for introducing feed fluid into said inlet and into said tube at a point between said inlet and said outlet, and means responsive to temperature of said tube adjacent said point for controlling said heating means and said intro? ducing means. 7

2. A control comprising a boiler tube having an inlet and an outlet, means for heating said tube to a low pre-determined temperature and then to a high pre-determinedtemperature, means for introducing feed fluid into said tube in synchronism and in phase both at said inlet and at a point between said inlet and said outlet, means responsive to temperature of said tube adjacent said point below said low pre-determined temperature for interrupting the operation of said introducing means, and means responsive to temperature of said tube adjacent said point above said high ire-determined temperature for interrupting the operation of said heating means.

3. A control comprising a boiler tube having an inlet, means for heating said tube, means for introducing feed fluid into said tube simultaneously at the inlet and at a point remote from the inlet, means responsive to a low temperature adjacent said point for interrupting the operation of said introducing means, and means responsive to a .high temperature adjacent said point for interrupting the operation of said heating means.

4. A control comprising a boiler tube, means for heating said tube when said tube is below a predetermined temperature, a thermostat between the ends of said tube and means for introducing a portion of the total feed fluid for said tube into said tube adjacent said thermostat when said tube is above a lower predetermined temperature, said heating means and said introducing means being controlled by said thermostat.

5. A control comprising a boiler tube, means for heating said tube, a thermostat between the ends of said tube, means for introducing a portion of the total feed fluid for said tube into said tube adjacent said thermostat, and means responsiveto said thermostat 'for stopping said heating means when said tube is at a first predetermined temperature,.and for stopping said introducing means when said tube is at a second, lower predetermined temperature.

6. A control comprising a boiler tube, a thermostat in thermal relation to said boiler tube, means for heating said tube, means controlled by'said thermostat for stopping said heating means, means for supplying feed fluid to said tube at two points one of said points being adjacent said thermostat, and means controlled by said thermostat for stopping said supplying means. 4

7. A control comprising a boiler tube, a thermostat in thermal relation to said tube, means for heating said tube, means responsive to said thermostat for interrupting said heating means at a high temperature, means for supplying feed fluid to said tube at two points one of said points being adjacent said thermostat, and means responsive to said thermostat for interrupting said supplying means at a low temperature.

8. A control comprising a boiler tube having an inlet, means responsive to temperature at an intermediate point of said tube for supplying feed fluid thereto at said point and at said inlet; means responsive to temperature at said point of said tube for heating said tube, and means responsive to pressure in said tube for interrupting both said heating means and said supplying means.

9. A control comprising a boiler tube having an inlet, means responsive to temperature of said tube at an intermediate point thereof, means for heating said tube in response to said responsive means, means for introducing feed fluid into said tube at said inlet and adjacent said point in response to said responsive means, and means responsive to pressure in said tube for stopping both said heating means and said introducing means.

10. A control comprising a boiler tube having a primary inletat one end, an outlet at the other end, and a secondary inlet between said primary inlet and said outlet, means for simultaneously introducing feed fluid into said primary inlet and said secondary inlet, a thermostat between said secondary inlet and said outlet, means controlled by said thermostat for heating said tube, and means controlled by said thermostat for regulat-. ing said introducing means.

11. A control comprising a boiler tube having a primary inlet at oneend, an outlet at the other end, and a secondary inlet between said primary inlet and said outlet, means for simultaneously introducing feed fluid into said primary inlet and said secondary inlet, a thermostat between said secondary inlet and said outlet, means controlled by said thermostat for heating said tube, means controlled by said thermostat for regulating said introducing means, and means responsive to presfirst predetermined temp sure in said tube for interrupting both said introducing means and said heating means.

12. A control comprising a boiler tube having a primary inlet adjacent an end and a secondary inlet adjacent the other end adapted to operate at varying temperature, means effective up to a erature adjacent said secondary inlet for heating said tube, means eflective between said first predetermined temperature and a second predetermined temperature adjacent said secondary inlet for heating said tube and supplying feed fluid to said primary and secondary inlets, and means efiective above said second predetermined temperature for supplying feed fluid to said primary and secondary inlets.

13. A control comprising a boiler tube having a secondary inlet between the ends thereof, means effective between a first predetermined temperature and a second predetermined temperature adjacent said secondary inlet for heating said tube and supplying feed fluid to said secondary inlet, means effective below said first predeterminedtemperature for only heating said tube,

and means effective above said second predeter-.

mined temperature for only supplying feed fluid to said secondary inlet. v

14. A control comprising a boiler tube having a primary inlet and having a secondary inlet between the ends thereof, means effective between a first predetermined temperature adjacent said secondary inlet and a second predetermined temperature adjacent said secondary inlet for heating said tube and supplying feed fluid thereto at said primary and secondary inlets, means efiective below said first predetermined temperature for only heating said tube, means effective above said second predetermined temperature for only supplying feed fluid to said tube, and means responsive to a predetermined pressure in said tube for stopping said heating means and said supplying means.

15. A control comprising a relatively long tube having a primary inlet at one end thereof, an outlet at the other end thereof, and a secondary irdet between the ends thereof, means for heating said ube, means for introducing feed fluid simultaneously into said primary inlet and into said secondary inlet, a thermostat in thermal relation to said tube between said secondary inlet and said outlet, means responsive to said thermostat below a first predetermined temperature for interrupting said introducing means, means responsive to said thermostat above a second predetermined temperature for interrupting said heating means, and means responsive to a predetermined pressure in said tube for interrupting said heating means and said introducing means.

16. A control comprising a tube into one end of which feed fluid is forced and from the other end of which vapor issues, means for heating said tube, a conduit for conveying a portion of the feed fluid directly to a point of the heated tube where vapor is contained, and a thermostat subject to vapor temperature near said point of said tube, said thermostat serving to control the operation of the feed fluid forcing means.

17.,A control comprising a feed fluid pumping means supplying feed fluid to a heated tube, said tube being arranged to receive feed fluid at one end and to deliver vapor at its other end, a conduit for conveying a portion of the feed fluid directly to a point in said heated tube distant from its inlet end, and a thermostat arranged in thermal relationship with said heated tube adjacent said point, said thermostat serving to control the operation of said feed fluid pumping means.

18. A control comprising a feed fluid pumpsupplying feed fluid to an evaporating tube, said tube being subjected to heat and receiving the main portion of the feed fluid at its inlet end and heating said fluid thereby converting it into a vapor which is delivered from the outlet end of said heated tube, a by-pass tube in communication,

with said feed fluid pump for conveying a small portion of the feed fluid into the heated tube at a point not far from its delivery end, and a thermostat subject to vapor temperature in that portion of said heated tube lying between the juncture of said by-pass tube with said heated tube and the outlet end of said heated tube, said thermostat serving to control the operation of said fluid pump.

19. A control comprising a feed fluid pump arranged to supply feed fluid to a heating coil, said coil comprising a long tube having an inlet for feed fluid and an outlet for vapor; the greater portion of said feed fluid entering said heating tube at the inlet and a minor portion entering said heating tube at a point not distant from the outlet, and a thermostat subject to vapor temperature in that portion of said heating tube lying between the outlet of said heating tube and the point at which the minor portion of the feed fluid enters; said thermostat being arranged to control the operation of said feed fluid pump.

20. A control comprising a tube having an inlet end for feed fluid and an outlet end for vapor; means for imparting heat to said tube whereby vapor is produced; means for supplying feed water to said tube, said supply of feed water being divided into two streams, the major portion entering at the inlet end of said tube and a minor portion entering the vapor region of said tube; and a thermostat subject to vapor temperature in a portion of said tube, said portion lying between the entry point of the minor flow of feed water and the delivery endof said heating tube.

21. A controlin which vapor is produced by forcing feed fluid into one end of a heating tube such that vapor issues from the other end of said tube; a thermostat subject to vapor temperature in a portion of said heating tube near said other end, said thermostat serving to control the flow of said feed fluid: and a by-pass conduit conveying a minor portionof said feed fluid into said heating tube a short distance from said thermostat.

' 22. A'control comprising a tube having an inlet end for feed fluid and an outlet end for vapor, means for imparting heat to said tube whereby vapor is produced, means for supplying feed fluid to said tube, said supply of feed fluid being divided into two streams, the major portion entering at the inlet end of said tube, and the minor portion entering the vapor region of said tube, a thermostat subject to vaportemperature in a portion of said tube, said minor portion of feed fluid acting directly upon and immediately influencing said thermostat, said thermostat serving to control said means for supplying feed fluid to. said tube.

23. A control comprising a boiler tube, feed fluid forcing means; a thermostat for controlling said means, said thermostat being responsive to a fluid temperature in said boiler tube, such fluid temperature being the resultant of the mixture of two portions of feed fiuid,'means for causing one of said portions of feed fluid to traverse the major portion of the boiler tube and the other of said portions of feed fluid to flow directly from the feed fluid forcing means without traversing the major portion of the boiler tube.

24. A control. comprising a heating tube, a burner for imparting heat to said tube, a feed pump for supplying feed fluid to said tube, a thermostat for controlling said feed pump and said burner, said thermostat being subject to the resultant temperature of the mixture of two portions of the fluid within said tube, one portion of which has traversed the entire'length of said tube and the other portion of which has passed directly from said feed pump without traversing the entire length of said tube.

25. A control comprising a heating tube, a burner for supplying heat to said tube, a feed pump for supplying feed fluid to said tube, said feed fluid being divided into two paths, one of which traverses the entire length of said tube and the other of which passes directly from the feed pump into an intermediary point in said tube, a thermostat subject to the resultant temperature of the combination of the fluids flowing the said two paths, said thermostat serving to control the operation of said feed pump and 'said burner.

26. A control comprising a heating tube, a burner for imparting heat to said tube, a feed pump for supplying feed fluid to said tube, a thermostat subject to the vapor temperature adjacent the outlet end of said tube and serving to control the operation of said burner and said feed pump, the temperature of said thermostat being determined by the mixture of two flows of fluid, one of which has passed through said tube and the other of which has come directly from said feed pump.

27. A control comprising a long tube having a primary inlet, a secondary inlet and an outlet, means for heating said tube, means for introducing feed fluid into said primary inlet and said secondary inlet in synchronism and in phase, and means responsive to temperature adjacent said secondary inlet for controlling said heating means and said introducing means.

28. A control for a forced circulation boiler having a primary inlet, a secondary inlet, and an outlet, comprising means for introducing feed fluid into said primary and secondary inlets in synchronism and in phase, and thermally respon-,

sive means adjacent said secondary inlet for controlling said introducing means.

29. A control comprising a long, heated tube, a thermostat between the ends of said tube, and means controlled by said thermostat for simultaneously and in phase introducing feed fluid into said tube near one end and into said tube near said thermostat to have a prompt efiect on said thermostat.

30. A control comprising a tube one end of which is relatively cold and the other end of which is relatively hot, thermally responsive means between the ends of said tube, and means controlled by said responsive means for concurrently supplying feed fluid to said relatively cold end and to said tube-adjacent said responsive means.

WILLIAM J. BESLER. 

